I am, and I don't know which ones to try (since I don't play computer games) (obvi).
So...at the risk of sounding completely wonk, who's the Herrmann or Goldsmith of game soundtracks?

Well, game soundtracks are varied, more or less like film music, but due to the vast technological limitations since it was born up til today, the genre turns to be most of the time "chiptunes" or computerized music. However, that doesn't mean, just because it's bleeps and bloops, that there can't be good music in chiptunes.. in fact, you'd be surprised, I was. Music, computerized or not, is still music, even with limitations, and a good composition and melody can still sound good beneath a "cheap" computer and that used to be the case. Hell, for example, composer Koichi Sugiyama, known for the Dragon Quest franchise, was always a huge symphonic, orchestral composer, and nonetheless, he took the job of making music for Dragon Quest back in the 80s, with the limitations of NES chiptunes, but still having massive orchestral undertones.

I digress a lot, forgive me. But basically, it depends of what kind of music or genre you're looking for. If you're looking for orchestral sound in games - I can recommend you a few, starting by Afrika, by Wataru Hokojama. And a couple of others that I cannot think of right now - as the technology advanced, and full music was possible within games, a couple of games used orchestral tracks when the makers deemed it suitable. If you're wanting to know which people are the biggest names in videogame music, I could name you a few right now, and they're without a doubt the BIGGEST; starting with Nobuo Uematsu and Final Fantasy, which I also recommend you look, filled to the brims with wonderful, talented compositions. You'd be surprised. Another one, Yoko Shimomura, known for Mario & Luigi, Super Mario RPG, Kingdom Hearts, Street Fighter.. Koichi Sugiyama and his Dragon Quest compositions..

Obviously, I am quite biased towards orchestrated music in games, though I've had my fair share of listenings to chiptune music, too. Among the best known that you'd probably like, and I recommend, is the Megaman series, composed by so many people so I can't just say one.

Thank you for your very thorough answer!